Treating contact substances used for catalytic action.



PATENTED MAY 22, 1906.

ABPLIUATION FILED IEB.24, 1903. RENEWED NOV.2, 1903.

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TSTDUR- KTTSEE, OF PHILADELPHIA,

PENNSYLVANQTA, ASSTJGNQR- OF ONE- Specification of Letters Patent.

Tc'atented May 22, 1906.

Application filed February 24,1903. Renewed November 2, 1903. Serial No. 179,337.

To all whom it may concern:

' mostly manufactured by the so-called con tact process from the sulfurous-acid gas generated now mostly from pyrites. It is also well known that no matter how carefully the gas is purified before coming in contact with the catalytic mass foreign substances, such as arsenic, are carried over to the contact or catalytic mass, thereby retarding the catalytic action often to such an extent that the mass becomes entirely useless.

, To renovate the contact substances, which in most cases consist of finely-divided plati- 'num, generally carried by a support, such as asbestos, the platinum in some cases is agam dissolved in the combined acids-nitric and hydrochloric-and reduced with the aid of heat on the carrier. In some instances the platinum istreated withsteam in combination with different gases, so as to restore again its activity. This process did not meet with entire success, and it is the aim of my invention to substitute for the processes used to-day a method whereby the foreign substances detrimental to the catalytic action of the contact .mass are eliminated. Platinum, no matter in how finely a divided state, will not deteriorate, oxidize, or be otherwise dissolved in the electrolytic apparatus through the action of the. electric current, whereas arsenic,

mercury, phosphorus, antimony, and metals of the same class, substances known as contact poisons andgenerally injuriously affecting the catalytic action, are readily dissolved and oxidized in such an electrolytic appa ratus no matter if the electrolyte of such cell consists only of'diluted sulfuric acid; and my present invention relates to the application of electric currents on a contact substance exposed to contact poisons or having lostentirely its catalytic action or the catalytic action of which has been impaired through foreign substances, such as arsenic, mercury,

phosphorus, &c.

Coming now to the my invention, it is referred that the elec trolytic a paratus s ould be constructed as follows: ne electrode should consist of a platinum support, and the other electrode may consist of copper but where the greater expense of platinum over copper is not too great a-drawback both electrodes should consist of platinum. The first-named electrode should preferably be laid at the bottom of the cell in a manner so as to act as a support for the contact mass if no other support is present. It is preferred that the electrolytic apparatus should consist of two \com artments, and the second electrode shal be placed in the secondcompartment. As an electrolyte sulfuric acid, chemically, pure,

practical application of;

may advantageously be employed. On top of the first-named electrode the contact mass to be purified shall be placed in a manner so that the same shall make an electrical contact with the electrode pro or. This electrode serves as the anode of t e a paratus and is connected to the positive p0 e of the charging-circuit. The second electrode serveszas the cathode of the apparatus and is connectedto the negative pole of the charging circuit. The voltage needed is about from four to six volts, iii accordance with the resistance of the apparatus and the greater or lesser amperage per square inch expdsed. It is only necessary to send a curre density through the apparausequal to one ampere for each ounce of contact mass, and the time to urify the same entirely varies from one to t ree hours.

I give proved;

these figures as experiments have but it is obvious that the same may 'be altered to suit requirements in each and every particular. case. In such instances where a greatamount of contact masshas to be purified at one and the same time a numher ofnsnch apparatus may be employed and may be connected in series with each other.

Truthe drawing, which illustrates in crosssection an electrolytic cell of a construction as preferably used, A is the'containing vessel; B, the electrolyte; C, the negative electrodeg i) the positive electrode; 11, the contact mash to be purified, and d the porous support for D and d. This porous support acts as adivision for the apparatus and should contain part of the electrolyte. It is preferred that if the arrangement as illustrated is carried out the positive electrodeD desired, the positive or negative electrode shall be formed of platinum wires 'a manner so that the same shall-form ametwork, this for the reason that if the contact would be solid throughout the electrolytic action would only be on the conductor and not on the contact mass, as desired.

'- It. is obvious that an electrolytic apparatus may be constructedof any desired design, and the arrangement herein illustrated is given so as to enable persons not familiar with the construction of electrolytic apparatus to use this my invention.

If desired, the porous support ma be dispensed with and the positive electro e placed at the bottom and the negative on top, ,or, if

may be contained in a receptacle such as a porous cup.

'It is not the aim of my invention to describe and make a'partic'ular kind of electrolytic apparatus, and I have selected, as said above, the form as illustrated because I found the same'convenient. in my experi ments.

I have described the processof renovating contact substances with the aid of electric current b ut' it is obvious that this contact mass can be made the electrode of an electher obvious that in such cases the destructtrolytic apparatus during the time of the production oi the sulfuric acid, and it is furiveinfluence of the contact poison is entirel'y obviated.

Indo not take into consideration in the latter arrangement the fact that the oxygen gases generated rnay "be made. useful and that the. hydrogen gases generated may be carried off by any suitable-means.

Having 'novvfdescribeglany invention, what I claim as new, and'de's'ire to secure by Letters Patent, is-

1. The process-ofreg'enerating contact substances for catalytic action which consists in subjecting said contact substances to the-action of an electric current;said substances being made part of the anode of an electrolytic apparatus.

2. The process of rcir'npnrting to platinum contacts the catalylicipower they formerly possessed, which consists therein that such platinum contacts 'lljatljgfltlfi part of. the anode through cont-act poisons such as arsenic and the like, which consists in providing such contact mass with an electrode, placing said mass with its electrode in an electrolytic cell provided with a second electrode and causing currents of electricity to pass through said apparatus, the contact mass with its electrode being made the an de of said cell.

4. The process 0 eliminating the contact poison from contact masses, which consists in making said contact masses part of the anode of an electrolytic apparatus and sending at the same time currents of electricity through said apparatus.

5. The process of extracting the contact poison or poisons from contact masses used for catalytic action which consists in mak ing said contact masses part of an electrode of anelectrolytic apparatus and passing currents of electricity through said apparatus in a manner so that said contact poison shall be oxidized or dissolved out of said mass.

6. The method of preventing substances known as contact poisons from destroying the catalytic action of contact masses which consists in subjecting said masses to the electrolytic action of anclectric current, said contact masses forming part of or being in contact with the anode of an electrolytic apparatus.

7. The process which consists therein. that a contact mass is made part of the anode of an electrolytic apparatus during the time that gases, adapted to be oxidized through the catalytic action of said mass, are brought in contact with same, whereby the destructive influence of the contact poisons carried by said gases is counteracted.

In testimony whereof I hereby sign my name, in the presence cl two subscribing witnesses, this 21st day of February, A. D. 1903.

ISIDOR KITSEE.

\Vitnesscs Em'ru P. STILLEY, CHAS. KRnssnNBUcH. 

